双煤层不规则煤柱应力—能量演化规律及防冲技术研究

煤矿开采遗留煤柱区域往往是高应力和能量聚集区,多煤层开采条件下,当上部遗留煤柱与工作面煤柱重叠时,多重应力作用下煤柱区应力分布及能量演化更为复杂,工作面回采过程中易发生动力现象.以某矿双煤层开采遗留不规则煤柱区开采为背景,采用数值模拟和工程实践等方法,研究了工作面开采过程中煤柱区的应力分布、能量演化规律,建立了不规则煤...

Study on stress-energy evolution law of irregular coal pillar in double coal seams and anti-scouring technology

Coal pillar area left by coal mining is often high stress and energy accumulation area.Under the condition of multi seam mining,when the upper remaining coal pillar overlaps with the coal pillar of the working face,the stress distribution and energy evolution of the coal pillar area under the action of multiple stresses are more complex,and the dynamic phenomenon is easy to occur in the process of mining.Based on the mining of irregular pillar area left by double seam mining in a mine,this paper studied the stress distribution and energy evolution law of pillar area in the mining process of working face by using numerical simulation and engineering practice,and established the impact risk monitoring system of irregular pillar area,formulated the targeted anti impact scheme.The results showed that,the degree of stress concentration in the irregular coal pillar area is highly affected by mining,and the high static load in the coal pillar is the main factor affecting the impact risk of the working face;when the working face is close to the coal pillar,the degree of strain energy accumulation in the"double layer"coal pillar is significantly higher than that in the single layer coal pillar under the goaf;field microseismic analysis showed that high energy events are mostly distributed in coal seam,and coal pillar is the main body of energy accumulation and release;the results of drilling cuttings method and on-line stress monitoring showed that the coal pillar area is a high stress concentration area.According to the results of numerical simulation and field monitoring,a large diameter pressure relief scheme is proposed and verified.